Reconstruction of multi-animal PET acquisitions with anisotropically variant PSF.

Among other factors such as random, attenuation and scatter corrections, uniform spatial resolution is key to performing accurate quantitative studies in Positron emission tomography (PET). Particularly in preclinical PET studies involving simultaneous acquisition of multiple animals, the degradation of image resolution due to the depth of interaction (DOI) effect far from the center of the Field of View (FOV) becomes a significant concern. In this work, we incorporated a spatially-variant resolution model into a real time iterative reconstruction code to obtain accurate images of multi-animal acquisition. We estimated the spatially variant point spread function (SV-PSF) across the FOV using measurements and Monte Carlo (MC) simulations. The SV-PSF obtained was implemented in a GPU-based Ordered subset expectation maximization (OSEM) reconstruction code, which includes scatter, attenuation and random corrections. The method was evaluated with acquisitions from two preclinical PET/CT scanners of the SEDECAL Argus family: a Derenzo phantom placed 2 cm off center in the 4R-SuperArgus, and a multi-animal study with 4 mice in the 6R-SuperArgus. The SV-PSF reconstructions showed uniform spatial resolution without significant increase in reconstruction time, with superior image quality compared to the uniform PSF model.

Vaginal neutrophil infiltration is contingent on ovarian cycle phase and independent of pathogen infection.

The mucosa of the female reproductive tract must reconcile the presence of commensal microbiota and the transit of exogenous spermatozoa with the elimination of sexually transmitted pathogens. In the vagina, neutrophils are the principal cellular arm of innate immunity and constitute the first line of protection in response to infections or injury. Neutrophils are absent from the vaginal lumen during the ovulatory phase, probably to allow sperm to fertilize; however, the mechanisms that regulate neutrophil influx to the vagina in response to aggressions remain controversial. We have used mouse inseminations and infections of Neisseria gonorrhoeae, Candida albicans, Trichomonas vaginalis, and HSV-2 models. We demonstrate that neutrophil infiltration of the vaginal mucosa is distinctively contingent on the ovarian cycle phase and independent of the sperm and pathogen challenge, probably to prevent sperm from being attacked by neutrophils. Neutrophils extravasation is a multi-step cascade of events, which includes their adhesion through selectins (E, P and L) and integrins of the endothelial cells. We have discovered that cervical endothelial cells expressed selectin-E (SELE, CD62E) to favor neutrophils recruitment and estradiol down-regulated SELE expression during ovulation, which impaired neutrophil transendothelial migration and orchestrated sperm tolerance. Progesterone up-regulated SELE to restore surveillance after ovulation.

Did anomalous atmospheric circulation favor the spread of COVID-19 in Europe?

The current pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is having negative health, social and economic consequences worldwide. In Europe, the pandemic started to develop strongly at the end of February and beginning of March 2020. Subsequently, it spread over the continent, with special virulence in northern Italy and inland Spain. In this study we show that an unusual persistent anticyclonic situation prevailing in southwestern Europe during February 2020 (i.e. anomalously strong positive phase of the North Atlantic and Arctic Oscillations) could have resulted in favorable conditions, e.g., in terms of air temperature and humidity among other factors, in Italy and Spain for a quicker spread of the virus compared with the rest of the European countries. It seems plausible that the strong atmospheric stability and associated dry conditions that dominated in these regions may have favored the virus propagation, both outdoors and especially indoors, by short-range droplet and aerosol (airborne) transmission, or/and by changing social contact patterns. Later recent atmospheric circulation conditions in Europe (July 2020) and the U.S. (October 2020) seem to support our hypothesis, although further research is needed in order to evaluate other confounding variables. Interestingly, the atmospheric conditions during the Spanish flu pandemic in 1918 seem to have resembled at some stage with the current COVID-19 pandemic.

Impact of Physiological Signals Acquisition in the Emotional Support Provided in Learning Scenarios.

Physiological sensors can be used to detect changes in the emotional state of users with affective computing. This has lately been applied in the educational domain, aimed to better support learners during the learning process. For this purpose, we have developed the AICARP (Ambient Intelligence Context-aware Affective Recommender Platform) infrastructure, which detects changes in the emotional state of the user and provides personalized multisensorial support to help manage the emotional state by taking advantage of ambient intelligence features. We have developed a third version of this infrastructure, AICARP.V3, which addresses several problems detected in the data acquisition stage of the second version, (i.e., intrusion of the pulse sensor, poor resolution and low signal to noise ratio in the galvanic skin response sensor and slow response time of the temperature sensor) and extends the capabilities to integrate new actuators. This improved incorporates a new acquisition platform (shield) called PhyAS (Physiological Acquisition Shield), which reduces the number of control units to only one, and supports both gathering physiological signals with better precision and delivering multisensory feedback with more flexibility, by means of new actuators that can be added/discarded on top of just that single shield. The improvements in the quality of the acquired signals allow better recognition of the emotional states. Thereof, AICARP.V3 gives a more accurate personalized emotional support to the user, based on a rule-based approach that triggers multisensorial feedback, if necessary. This represents progress in solving an open problem: develop systems that perform as effectively as a human expert in a complex task such as the recognition of emotional states.

Citoquinas proinflamatorias en la grasa articular y subcutánea del muslo en pacientes artrósicos / Pro-inflammatory cytokines in the knee fat pad and subcutaneous fat of the thigh in osteoarthritic patients

Resumen: Objetivo: Analizar el nivel de citoquinas proinflamatorias en la grasa articular del paquete adiposo en pacientes con gonartrosis, en relación con la grasa subcutánea del muslo. Material y métodos: Efectuamos un estudio de grasa del paquete adiposo articular de la rodilla afectada de artrosis y de la grasa subcutánea del muslo del mismo lado, a la mayor distancia de la articulación en seis pacientes con gonartrosis grave, con una edad media de 68 años (rango: 55-81 años). De las muestras de grasa se obtuvieron las células mesenquimales progenitoras. Los sobrenadantes de células mesenquimales obtenidas se utilizaron para analizar factores inflamatorios (IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13, IL15) y angiogénicos (VEGF, PDGF bb), así como citoquinas inmunomoduladoras (IP-10 e INF-γ) y se compararon las medias de dos muestras. Resultados: El análisis cuantitativo reveló una disminución significativa (p < 0.05) de IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 y un aumento de IL15 en la grasa de Hoffa frente al tejido adiposo subcutáneo. Del mismo modo, el análisis de factores angiógenicos como VEGF y PDGF bb, al igual que los factores IP-10 e INF-γ presentaron una disminución significativa en la grasa de Hoffa (p < 0.05) frente al tejido adiposo subcutáneo. Discusión: Las células mesenquimales del paquete adiposo articular de la rodilla artrósica grave muestran una disminución significativa de citoquinas inflamatorias, aun en el estado crónico, y una disminución significativa de factores angiogénicos y citoquinas inmunomoduladoras (IP10 e INF).

Abstract: Objective: To analyze the level of pro-inflammatory cytokines in osteoarthritis knee joint fat pad in relation to the subcutaneous fat of the thigh. Material and methods: We performed a study of fat of the knee joint adipose affected of osteoarthritis and subcutaneous fat of the thigh of the same side to the greater distance of the joint in six patients with severe gonarthrosis, with a mean age of 68 years (range: 55-81 years). From the fat samples the progenitor mesenchymal cells were obtained. The supernatants of mesenchymal cells obtained to analyze inflammatory factors (IL-1b, IL6, IL9, IL1ra, IL12, IL13, IL15) and angiogenic (VEGF, PDGF bb) and immunomodulatory cytokines (IP-10 and INF-γ) means of two samples. Results: Quantitative analysis revealed a significant (p < 0.05) decrease in IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 and increase of IL15 in Hoffa fat pad versus subcutaneous adipose tissue. Likewise, the analysis of angiogenic factors such as VEGF and PDGF, as well as factors IP-10 and INF-γ presented a significant decrease (p < 0.05) in Hoffa fat pad versus subcutaneous adipose tissue. Discussion: Mesenchymal cells from the adipose tissue of the severe osteoarthritic knee show a significant decrease in inflammatory cytokines even in the chronic state and a significant decrease in angiogenic factors and immunomodulatory cytokines (IP10 and INF).

[Pro-inflammatory cytokines in the knee fat pad and subcutaneous fat of the thigh in osteoarthritic patients]. / Citoquinas proinflamatorias en la grasa articular y subcutánea del muslo en pacientes artrósicos.

OBJECTIVE: To analyze the level of pro-inflammatory cytokines in osteoarthritis knee joint fat pad in relation to the subcutaneous fat of the thigh. MATERIAL AND METHODS: We performed a study of fat of the knee joint adipose affected of osteoarthritis and subcutaneous fat of the thigh of the same side to the greater distance of the joint in six patients with severe gonarthrosis, with a mean age of 68 years (range: 55-81 years). From the fat samples the progenitor mesenchymal cells were obtained. The supernatants of mesenchymal cells obtained to analyze inflammatory factors (IL-1b, IL6, IL9, IL1ra, IL12, IL13, IL15) and angiogenic (VEGF, PDGF bb) and immunomodulatory cytokines (IP-10 and INF-) means of two samples. RESULTS: Quantitative analysis revealed a significant (p 0.05) decrease in IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 and increase of IL15 in Hoffa fat pad versus subcutaneous adipose tissue. Likewise, the analysis of angiogenic factors such as VEGF and PDGF, as well as factors IP-10 and INF- presented a significant decrease (p 0.05) in Hoffa fat pad versus subcutaneous adipose tissue. DISCUSSION: Mesenchymal cells from the adipose tissue of the severe osteoarthritic knee show a significant decrease in inflammatory cytokines even in the chronic state and a significant decrease in angiogenic factors and immunomodulatory cytokines (IP10 and INF).

OBJETIVO: Analizar el nivel de citoquinas proinflamatorias en la grasa articular del paquete adiposo en pacientes con gonartrosis, en relación con la grasa subcutánea del muslo. MATERIAL Y MÉTODOS: Efectuamos un estudio de grasa del paquete adiposo articular de la rodilla afectada de artrosis y de la grasa subcutánea del muslo del mismo lado, a la mayor distancia de la articulación en seis pacientes con gonartrosis grave, con una edad media de 68 años (rango: 55-81 años). De las muestras de grasa se obtuvieron las células mesenquimales progenitoras. Los sobrenadantes de células mesenquimales obtenidas se utilizaron para analizar factores inflamatorios (IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13, IL15) y angiogénicos (VEGF, PDGF bb), así como citoquinas inmunomoduladoras (IP-10 e INF-) y se compararon las medias de dos muestras. RESULTADOS: El análisis cuantitativo reveló una disminución significativa (p 0.05) de IL-1b, IL6, IL8, IL9, IL1ra, IL12, IL13 y un aumento de IL15 en la grasa de Hoffa frente al tejido adiposo subcutáneo. Del mismo modo, el análisis de factores angiógenicos como VEGF y PDGF bb, al igual que los factores IP-10 e INF- presentaron una disminución significativa en la grasa de Hoffa (p 0.05) frente al tejido adiposo subcutáneo. DISCUSIÓN: Las células mesenquimales del paquete adiposo articular de la rodilla artrósica grave muestran una disminución significativa de citoquinas inflamatorias, aun en el estado crónico, y una disminución significativa de factores angiogénicos y citoquinas inmunomoduladoras (IP10 e INF).

Computed Tomography-Based Biomarker for Longitudinal Assessment of Disease Burden in Pulmonary Tuberculosis.

PURPOSE: Computed tomography (CT) images enable capturing specific manifestations of tuberculosis (TB) that are undetectable using common diagnostic tests, which suffer from limited specificity. In this study, we aimed to automatically quantify the burden of Mycobacterium tuberculosis (Mtb) using biomarkers extracted from x-ray CT images. PROCEDURES: Nine macaques were aerosol-infected with Mtb and treated with various antibiotic cocktails. Chest CT scans were acquired in all animals at specific times independently of disease progression. First, a fully automatic segmentation of the healthy lungs from the acquired chest CT volumes was performed and air-like structures were extracted. Next, unsegmented pulmonary regions corresponding to damaged parenchymal tissue and TB lesions were included. CT biomarkers were extracted by classification of the probability distribution of the intensity of the segmented images into three tissue types: (1) Healthy tissue, parenchyma free from infection; (2) soft diseased tissue, and (3) hard diseased tissue. The probability distribution of tissue intensities was assumed to follow a Gaussian mixture model. The thresholds identifying each region were automatically computed using an expectation-maximization algorithm. RESULTS: The estimated longitudinal course of TB infection shows that subjects that have followed the same antibiotic treatment present a similar response (relative change in the diseased volume) with respect to baseline. More interestingly, the correlation between the diseased volume (soft tissue + hard tissue), which was manually delineated by an expert, and the automatically extracted volume with the proposed method was very strong (R2 ≈ 0.8). CONCLUSIONS: We present a methodology that is suitable for automatic extraction of a radiological biomarker from CT images for TB disease burden. The method could be used to describe the longitudinal evolution of Mtb infection in a clinical trial devoted to the design of new drugs.

Intrathecal administration of autologous bone marrow stromal cells improves neuropathic pain in patients with spinal cord injury.

Neuropathic pain (NP) is highly disabling, responds poorly to pharmacological treatment, and represents a significant cause of decreased quality of life in patients suffering from spinal cord injury (SCI). In recent years, cell therapy with autologous mesenchymal stromal cells (MSCs) has been considered as a potential therapeutic weapon in this entity. Ten patients suffering chronic SCI received 100 million MSCs into subarachnoid space by lumbar puncture (month 1 of the study) and this procedure was repeated at months 4 and 7 until reaching a total doses of 300 million MSCs. Intensity of NP was measured by standard numerical rating scale (VAS) from 0 to 10, recording scores previous to the first MSCs administration and monthly, until month 10 of follow-up. Months 1, 4, 7 and 10 of the study were selected as time points in order to a statistical analysis by the nonparametric Wilcoxon rank test. Our results showed significant and progressive improvement in NP intensity after the first administration of MSCs (p: 0.003). This study supports the benefit of intrathecal administration of autologous MSCs for the treatment of NP in patients with SCI.

Selective sentinel lymph node biopsy in male breast cancer. / Biopsia selectiva del ganglio centinela en el cáncer de mama del varón.

OBJECTIVE: To evaluate the reproducibility of the sentinel lymph node (SLN) technique in male breast cancer. MATERIAL AND METHODS: We retrospectively analysed 21 male patients diagnosed with breast cancer in our hospital from 2008 to 2016 with, at least, 18 months follow-up. Fifteen patients underwent selective sentinel lymph node biopsy (SLNB) following the usual protocols with peritumoral injection of 18.5-111MBq of 99mTc-nanocoloides and acquisition of planar images 2hours after the injection. In 2 cases it was necessary to perform a SPECT/CT to locate the SLN. Immunohistochemistry and molecular techniques (OSNA) were used for their analysis. Six patients did not undergo SLNB because they had pathological nodes or distant disease at the time of diagnosis. RESULTS: SLNB was performed in 15 patients. The SLN was negative in 6 patients and positive in the remaining 9. Three patients with positive SLNB did not need axillary lymphadenectomy because of the low number of copies by molecular analysis OSNA. Axillary lymphadenectomy was performed in the remaining 6 patients with the result of 4 positive axillary lymphadenectomies and 2 that did not show further extension of the disease. CONCLUSIONS: According to our experience, SLNB in males is a reproducible, useful, safe and reliable technique which avoids unnecessary axillary lymphadenectomy and prevents the appearance of undesirable effects.

Migración intraarticular del bloqueo óseo tibial tras la reconstrucción del ligamento cruzado anterior con injerto hueso-tendón-hueso / Intra-articular migration of a tibial bone block after an anterior cruciate ligament reconstruction using a bone-tendon-bone graft

Resumen: Presentamos el caso de una paciente que tras una reconstrucción del ligamento cruzado anterior (LCA) con injerto hueso-tendón-hueso (HTH) presentó una protrusión intraarticular del bloque óseo tibial en la radiografía postoperatoria de control. Se postuló la divergencia entre el túnel óseo tibial y el tornillo de interferencia como causa fundamental de la migración del injerto. Varios trabajos en modelos animales asocian dicho supuesto a una menor resistencia a la tracción. No se ha encontrado en la bibliografía médica publicada hasta la fecha ningún reporte clínico que describa esta complicación.

Abstract: We report the case of a patient that presented an intra-articular protrusion of the tibial bone block after an arthroscopically-assisted ACL reconstruction using a bone-patellar tendon-bone graft. The divergence between the tunnel and the screw was thought to be the reason of the migration. There are several animal-model studies that evidence a relationship between the decreased fixation of the graft and the tunnel-screw divergence. To the best of our knowledge, this is the first report of this complication.

Molecular markers of putative spermatogonial stem cells in the domestic cat.

Spermatogonial stem cells (SSCs) are an important tool for fertility preservation and species conservation. The ability to expand SSCs by in vitro culture is a crucial premise for their use in assisted reproduction. Because SSCs represent a small proportion of the germ cells in the adult testis, culture success is aided by pre-enrichment through sorting techniques based on cell surface-specific markers. Given the importance of the domestic cat as a model for conservation of endangered wild felids, herein we sought to examine culture conditions as well as molecular markers for cat SSCs. Using a cell culture medium for mouse SSCs supplemented with glial cell-derived neurotrophic factor (GDNF), germ cells from prepuberal cat testes remained viable in culture for up to 43 days. Immunohistochemistry for promyelocytic leukaemia zinc finger (PLZF) protein on foetal, prepuberal and adult testis sections revealed a pattern of expression consistent with the labelling of undifferentiated spermatogonia. Fluorescence-activated cell sorting (FACS) with an antibody against epithelial cell adhesion molecule (EPCAM) was used to sort live cells. Then, the gene expression profile of EPCAM-sorted cells was investigated through RT-qPCR. Notably, EPCAM (+) cells expressed relatively high levels of CKIT (CD117), a surface protein typically expressed in differentiating germ cells but not SSCs. Conversely, EPCAM (-) cells expressed relatively high levels of POU domain class 5 transcription factor 1 (POU1F5 or OCT4), clearly a germ line stem cell marker. These results suggest that cat SSCs would probably be found within the population of EPCAM (-) cells. Future studies should identify additional surface markers that alone or in combination can be used to further enrich SSCs from cat germ cells.

Role of the PDZ-scaffold protein NHERF1/EBP50 in cancer biology: from signaling regulation to clinical relevance.

The transmission of cellular information requires fine and subtle regulation of proteins that need to interact in a coordinated and specific way to form efficient signaling networks. The spatial and temporal coordination relies on scaffold proteins. Thanks to protein interaction domains such as PDZ domains, scaffold proteins organize multiprotein complexes enabling the proper transmission of cellular information through intracellular networks. NHERF1/EBP50 is a PDZ-scaffold protein that was initially identified as an organizer and regulator of transporters and channels at the apical side of epithelia through actin-binding ezrin-moesin-radixin proteins. Since, NHERF1/EBP50 has emerged as a major regulator of cancer signaling network by assembling cancer-related proteins. The PDZ-scaffold EBP50 carries either anti-tumor or pro-tumor functions, two antinomic functions dictated by EBP50 expression or subcellular localization. The dual function of NHERF1/EBP50 encompasses the regulation of several major signaling pathways engaged in cancer, including the receptor tyrosine kinases PDGFR and EGFR, PI3K/PTEN/AKT and Wnt-ß-catenin pathways.

[Intra-articular migration of a tibial bone block after an anterior cruciate ligament reconstruction using a bone-tendon-bone graft]. / Migración intraarticular del bloqueo óseo tibial tras la reconstrucción del ligamento cruzado anterior con injerto hueso-tendón-hueso.

We report the case of a patient that presented an intra-articular protrusion of the tibial bone block after an arthroscopically-assisted ACL reconstruction using a bone-patellar tendon-bone graft. The divergence between the tunnel and the screw was thought to be the reason of the migration. There are several animal-model studies that evidence a relationship between the decreased fixation of the graft and the tunnel-screw divergence. To the best of our knowledge, this is the first report of this complication.

Presentamos el caso de una paciente que tras una reconstrucción del ligamento cruzado anterior (LCA) con injerto hueso-tendón-hueso (HTH) presentó una protrusión intraarticular del bloque óseo tibial en la radiografía postoperatoria de control. Se postuló la divergencia entre el túnel óseo tibial y el tornillo de interferencia como causa fundamental de la migración del injerto. Varios trabajos en modelos animales asocian dicho supuesto a una menor resistencia a la tracción. No se ha encontrado en la bibliografía médica publicada hasta la fecha ningún reporte clínico que describa esta complicación.

[Pretibial pseudocyst after anterior cruciate ligament reconstruction with a biocomposite screw]. / Seudoquiste pretibial tras la reconstrucción del ligamento cruzado anterior con tornillo biocomposite.

We report the case of a patient who presented a pretibial extra-articular cyst two years after an arthroscopically assisted ACL reconstruction using an autologous bone-patellar tendon-bone graft. The tibial fixation was achieved with a bioabsorbable screw made of poly-L, D-lactic and -tricalcium phosphate (-TCP). A subcutaneous pseudocystic lesion was excised. It consisted of a capsular fibrous tissue with minimal milky fluid (1 ml) centrally. It penetrated into the tibial tunnel but did not communicate with the knee joint space. The histopathological analysis demonstrated fibrous tissue with multinucleated giant cells and refractile particles which suggested a foreign body reaction. After the surgery, the patient recovered perfectly well and he returned to his pre-injury level of physical activity in two months. To the best of our knowledge, this is the first report of this complication in a patient with a biocomposite screw made of poly-L, D-lactic and -tricalcium phosphate (-TCP).

Presentamos el caso de un paciente con un nódulo subcutáneo pretibial de unos 20 × 15 mm dos años después de la reconstrucción del ligamento cruzado anterior con un injerto autólogo hueso-tendón-hueso de tendón rotuliano fijado en la tibia con un tornillo de interferencia reabsorbible de ácido poli-D, L-láctico y fosfato -tricálcico. Se resecó una lesión seudoquística subcutánea con contenido líquido blanquecino y abundante fibrosis circundante, que penetraba en el túnel tibial sin comunicar con la articulación. El análisis anatomopatológico describió tejido fibroso con células multinucleadas y partículas refringentes, que sugería una reacción a cuerpo extraño. Después de la intervención, la sintomatología remitió y el individuo pudo recuperar su actividad deportiva previa en menos de dos meses. No se ha encontrado en la literatura médica publicada hasta la fecha ningún trabajo que describa esta complicación en un sujeto con un tornillo de interferencia tibial de ácido poli-D, L-láctico y fosfato -tricálcico.

[Non traumatic posterior instability in primary total knee replacement and its revision]. / Inestabilidad posterior no traumática de prótesis de rodilla primaria y su revisión.

BACKGROUND: Dislocation after total knee arthroplasty is a rare complication and a difficult problem to address. When the flexion gap is larger than the extension gap and the collateral ligaments are injured, instability and knee arthroplasty dislocation can occur. MATERIAL AND METHODS: We report the case of a patient presenting with a posterior dislocation of a posterior-stabilized prosthesis without trauma. Frank instability in varus stress test and a positive anterior drawer test with tibial internal rotation dismissed the conservative treatment. RESULTS: A constrained condylar prosthesis was used for the revision. He suffered a similar episode after a month, which demonstrated that the increase in the level of constraint was not enough to correct the severe asymmetric instability in flexion due to the damaged external structures. A rotating-hinge prosthesis was then implanted and the patient reported no additional episodes of instability. CONCLUSIONS: We made an exhaustive review of the literature, analyzed the possible causes that can lead to the tibiofemoral instability after a total knee arthroplasty and described some technical considerations.

La luxación tras la artroplastía de rodilla es una complicación poco frecuente y de difícil manejo. Una brecha en flexión demasiado grande asociada a una laxitud de los ligamentos colaterales puede llevar a la inestabilidad y a la luxación en flexión.

Seudoquiste pretibial tras la reconstrucción del ligamento cruzado anterior con tornillo biocomposite / Pretibial pseudocyst after anterior cruciate ligament reconstruction with a biocomposite screw

Resumen: Presentamos el caso de un paciente con un nódulo subcutáneo pretibial de unos 20 × 15 mm dos años después de la reconstrucción del ligamento cruzado anterior con un injerto autólogo hueso-tendón-hueso de tendón rotuliano fijado en la tibia con un tornillo de interferencia reabsorbible de ácido poli-D, L-láctico y fosfato β-tricálcico. Se resecó una lesión seudoquística subcutánea con contenido líquido blanquecino y abundante fibrosis circundante, que penetraba en el túnel tibial sin comunicar con la articulación. El análisis anatomopatológico describió tejido fibroso con células multinucleadas y partículas refringentes, que sugería una reacción a cuerpo extraño. Después de la intervención, la sintomatología remitió y el individuo pudo recuperar su actividad deportiva previa en menos de dos meses. No se ha encontrado en la literatura médica publicada hasta la fecha ningún trabajo que describa esta complicación en un sujeto con un tornillo de interferencia tibial de ácido poli-D, L-láctico y fosfato β-tricálcico.

Abstract: We report the case of a patient who presented a pretibial extra-articular cyst two years after an arthroscopically assisted ACL reconstruction using an autologous bone-patellar tendon-bone graft. The tibial fixation was achieved with a bioabsorbable screw made of poly-L, D-lactic and β-tricalcium phosphate (β-TCP). A subcutaneous pseudocystic lesion was excised. It consisted of a capsular fibrous tissue with minimal milky fluid (1 ml) centrally. It penetrated into the tibial tunnel but did not communicate with the knee joint space. The histopathological analysis demonstrated fibrous tissue with multinucleated giant cells and refractile particles which suggested a foreign body reaction. After the surgery, the patient recovered perfectly well and he returned to his pre-injury level of physical activity in two months. To the best of our knowledge, this is the first report of this complication in a patient with a biocomposite screw made of poly-L, D-lactic and β-tricalcium phosphate (β-TCP).

Influencia de la causa de revisión en el resultado tras revisión protésica de rodilla con implante varo-valgo constreñido / Influence of the cause of the revision on the outcome after revision knee arthroplasty with condylar constrained implant

Introducción. La artroplastia de revisión de rodilla es un procedimiento frecuente con resultados variables en función de la causa. Nuestro objetivo fue comparar los resultados clínicos y radiológicos en pacientes sometidos a revisión protésica tras infección frente aquellos con revisión por causa aséptica. Material y métodos. Se incluyeron 41 casos de revisión con el mismo implante constreñido varo-valgo. En todos los casos se realizó una valoración clínica (dolor, rango de movilidad, función mediante la escala KSS) y de complicaciones, así como un estudio radiológico. Se realizó un análisis comparativo de los resultados pre y postoperatorios y entre los grupos de causa séptica y aséptica. El seguimiento final medio fue de 6 años. Resultados. La movilidad al final del seguimiento mejoró una media de 17° de balance articular (p < 0,01). El KSS y el KSS funcional mejoraron significativamente respecto al preoperatorio. Radiológicamente, se restauró la interlínea articular y se corrigió el eje del miembro en todos los casos. Se encontraron radiolucencias en el 36,5% de los casos sin relación con la aparición de aflojamiento del implante. Se produjeron complicaciones en el 29,2% de los casos, siendo la mayoría relacionadas con la herida quirúrgica. La movilidad, el KSS, el KSS funcional y satisfacción al final del seguimiento fueron mejores en el grupo de pacientes de causa séptica. La supervivencia del implante fue del 95% al final del seguimiento. Conclusión. La artroplastia de revisión con implante constreñido varo-valgo es un procedimiento seguro y con buenos resultados a medio plazo independientemente de la causa del recambio (AU)

Introduction. Revision total knee arthroplasty (TKA) is a common procedure with varying results depending on the cause. Our objective was to compare the clinical and radiological outcomes in patients undergoing aseptic revision versus revision due to prosthetic infection. Material and methods. The study included 41 patients who underwent TKA revision with the same varus-valgus constrained implant. In all cases a clinical evaluation was performed including pain, range of motion (ROM), Knee Society Score (KSS), complications, as well as radiological study. A comparative analysis was performed on the pre- and postoperative results between septic and aseptic groups. The mean follow-up was 6 years. Results. ROM had a mean increase of 17 degrees (p<.01). KSS and functional KSS improved significantly postoperatively. In the radiological study, joint interline and limb alignment were restored in all cases. Radiolucencies were found in 36.5% of cases; however they were unrelated to the appearance of loosening of the implant. There were complications in 29.2% of cases, mostly related to the surgical wound. Mobility, KSS, KSS functional and satisfaction at follow-up were better in the septic group. Implant survival was 95% at follow-up. Conclusion. Revision arthroplasty with constrained varus-valgus implant is safe, and has successful mid-term results despite the cause of the replacement procedure (AU)